‘It is very sad news but he opens a door for his future with his family,’ he said. ‘Ryan has been at the training ground in recent days. We have been talking to him with (head of academy,) John McDermott.

‘He will be successful in whatever he does. He will always be a special player for me. He represents for me this change in all when we arrived at Tottenham.

Mason emerged through Tottenham’s youth academy before moving to Hull in 2016

‘Don’t worry Ryan, you’re going to be a successful person outside of the club,’ Pochettino said

‘The door is open for me to help him; and the club because we love him and Rachel and George and all his family. Don’t worry Ryan, you’re going to be a successful person outside of the club.’

Mason came through the ranks at Tottenham, where he made 70 appearances before being sold to Hull for £13million in August 2016.

He made a dramatic contribution to the start of Pochettino’s reign — coming off the bench to hit a long-range equaliser when Spurs were trailing Nottingham Forest in the League Cup in 2014.

Tottenham went on to record Pochettino’s first win in five matches as the new manager.

On New Year’s Eve, Mason shared a picture of the huge scar he was left with on his head

And since Mason announced his retirement, figures from within football have offered their condolences to the former Hull midfielder.

Cahill said he was left ‘devastated’ by the news and now Arsenal goalkeeper Petr Cech — himself the victim of a nasty head injury in 2006 — sent Mason a message of support.

‘Yesterday was a sad day for one incredible young man @RyanMason,’ the Arsenal goalkeeper wrote on Twitter.

‘Although his story didn’t finish with ultimate happy ending , his determination , attitude and bravery he’s shown during his recovery is something to be admired and an inspiration for others ! All the best Ryan.’